JP2019129663A - Estimation device and estimation method - Google Patents

Abstract

To provide an estimation device and an estimation method capable of estimating the permanent magnet temperature of a rotary machine, without performing any special control for the rotary machine during operation thereof.SOLUTION: An estimation arithmetic processing section has a first data application part for determining the inductance at the permanent magnet temperature from the basic wave component of a phase current taken out by waveform conversion processing, on the basis of first data indicating the relation between the permanent magnet temperature, the phase current, and the inductance of the rotary machine, a magnet magnetic flux calculation part for calculating the magnet magnetic flux from the basic wave component of phase current taken out by waveform conversion processing, the basic wave component of line-to-line voltage, the angular speed, the inductance determined in the first data application part, and the phase resistance of the rotary machine, and a second data application part for determining the permanent magnet temperature from the calculated magnet magnetic flux, on the basis of second data indicating the relation about the magnet magnetic flux for the permanent magnet temperature. The estimation arithmetic processing section determines the permanent magnet temperature by performing estimation arithmetic processing repeatedly.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an estimation apparatus and estimation method for estimating the permanent magnet temperature of a rotating machine.

  In a rotating machine equipped with a permanent magnet, such as a generator or an electric motor, the temperature of the permanent magnet in the rotating machine rises due to a loss generated inside the rotating machine due to driving. If the permanent magnet temperature rises excessively, the permanent magnet may be irreversibly demagnetized. In order to prevent such irreversible demagnetization, it is desirable to obtain the permanent magnet temperature and appropriately control the load current so as not to exceed the temperature at which the irreversible demagnetization occurs. However, if the permanent magnet of the rotating machine is provided on the rotor, or if there is no space for attaching the temperature detector due to requirements such as downsizing or high speed rotation, the temperature detector is attached to the permanent magnet It may be difficult to detect.

  In this regard, Patent Documents 1 and 2 below propose methods for estimating the permanent magnet temperature without directly detecting the permanent magnet temperature.

JP 2004-201425 A Patent No. 5823055

  However, in the estimation method of Patent Document 1, it is necessary to measure the current and voltage at that time after controlling the current phase of the rotating machine (motor) to 0. For example, the rotating machine used as a generator is a rectifier If the phase of the current cannot be controlled arbitrarily, such as when the rotation angle detector such as a resolver cannot be attached to the rotating machine or when it is connected to the rotating machine, highly accurate estimation of the permanent magnet temperature is performed. There is a problem that can not be done.

  Further, in the estimation method of Patent Document 2, it is necessary to temporarily reduce the current flowing to the rotating machine (motor) to zero and measure the induced voltage generated at that time, for example, the rotation used as a generator There is a problem that the permanent magnet temperature cannot be estimated when the current flowing through the rotating machine cannot be temporarily reduced to zero, such as when the power generation cannot be stopped in the machine.

  The present invention has been made in view of the above, and an estimation apparatus and estimation method capable of estimating the permanent magnet temperature of a rotating machine with high accuracy without performing special control on the rotating machine during operation of the rotating machine. Intended to provide.

  An estimation apparatus according to an aspect of the present invention is an estimation apparatus for estimating a permanent magnet temperature in a rotating machine including a permanent magnet, the storage storing the first data and the second data, and A current detector for detecting a phase current flowing through a rotating machine, a voltage detector for detecting a line voltage of the rotating machine, and an arithmetic unit, wherein the first data includes the temperature of the permanent magnet, and the phase The second data is data indicating a relationship between the permanent magnet temperature and the magnet magnetic flux, and the computing unit is configured to detect the phase detected from the current and the inductance of the rotating machine. A waveform conversion processing unit for extracting a fundamental wave component of the phase current from a current, and performing a waveform conversion process for extracting a fundamental wave component of the line voltage and an angular velocity of the rotating machine from the detected line voltage; and the permanent magnet Temperature And an estimation operation processing unit for performing an estimation operation process for determining the permanent current from the fundamental wave component of the phase current extracted by the waveform conversion process based on the first data. A first data application unit that determines the inductance at the magnet temperature, and a fundamental wave component of the phase current extracted by the waveform conversion process, a fundamental wave component of the line voltage, the angular velocity, and the first data application unit. A magnetic flux calculating unit for calculating the magnetic flux from the inductance and the phase resistance of the rotating machine, and second data for determining the permanent magnet temperature from the calculated magnetic flux based on the second data. And the estimation calculation processing unit initially sets the permanent magnet as the permanent magnet temperature when determining the inductance. Thereafter, when the permanent magnet temperature is determined and the inductance is determined by repeatedly performing the estimation calculation process using the permanent magnet temperature determined by the second data application unit. When the difference between the permanent magnet temperature used and the permanent magnet temperature determined by the estimation calculation process is within a predetermined range, the permanent magnet temperature determined by the estimation calculation process is estimated. It is comprised so that it may output as a permanent magnet temperature.

  According to the above configuration, the first data indicating the relationship between the permanent magnet temperature, the phase current, and the inductance of the rotating machine from the phase current flowing through the rotating machine and the line voltage of the rotating machine, and the magnetic flux with respect to the permanent magnet temperature. The permanent magnet temperature is calculated by the estimation operation process which is a convergence operation using the second data indicating the relationship. In this estimation calculation process, it is not necessary to control the current phase, and since the permanent magnet temperature is calculated from the measurable phase current and line voltage during rotation of the rotating machine, special control of the rotating machine is required. There is no need to do it. Therefore, the permanent magnet temperature of the rotating machine can be estimated with high accuracy without performing special control on the rotating machine during the operation of the rotating machine.

  The phase current and the line voltage used for the waveform conversion process may be values detected when the rotating machine is rotating and current is flowing through the rotating machine.

  The rotating machine may be a generator, and the generator may be electrically connected to a rectifier. When a rectifier is electrically connected to the generator, the current phase can not be controlled arbitrarily. On the other hand, in the above aspect, since it is not necessary to control the current phase arbitrarily, the permanent magnet temperature of the generator can be estimated with high accuracy even in a system in which a rectifier is connected to the generator.

  The estimation device includes a temperature detector that detects a coil temperature of the rotating machine, and the computing unit is a voltage between the lines detected when the rotating machine is rotating and no current flows in the rotating machine. And a second data correction unit that corrects the second data such that the magnet magnetic flux is calculated from the above and the calculated magnet magnetic flux becomes the magnet magnetic flux when the permanent magnet temperature is the coil temperature. Good. According to this, the second data can be corrected according to the individual difference of the magnet magnetic force of the permanent magnet attached to the rotating machine that estimates the permanent magnet temperature. Therefore, the permanent magnet temperature can be estimated more accurately.

  The estimation device may include a temperature detector that detects a coil temperature of the rotating machine, and the magnet magnetic flux calculation unit may correct the phase resistance based on the detected coil temperature. According to this, it is possible to correct the phase resistance of the rotating machine to a value when estimating the permanent magnet temperature. Therefore, the permanent magnet temperature can be estimated more accurately.

  An estimation method according to another aspect of the present invention is an estimation method for estimating a permanent magnet temperature in a rotating machine provided with a permanent magnet, which detects a phase current flowing through the rotating machine, and a line of the rotating machine Waveform conversion processing for detecting an inter-voltage, extracting a fundamental wave component of the phase current from the detected phase current, and extracting a fundamental wave component of the line voltage and an angular velocity of the rotating machine from the detected line voltage The estimation calculation process for estimating the permanent magnet temperature is performed, and the estimation calculation process indicates a relationship between the permanent magnet temperature, the phase current, and the inductance of the rotating machine. Based on first data, the inductance at the permanent magnet temperature is determined from the fundamental wave component of the phase current extracted by the waveform conversion process, and the phase extracted by the waveform conversion process The magnetic flux is calculated from the fundamental wave component of the flow, the fundamental wave component of the line voltage, the angular velocity, the determined inductance, and the phase resistance of the rotating machine, and shows the relationship with respect to the permanent magnet temperature. Based on the second data, including the process of determining the permanent magnet temperature from the calculated magnet magnetic flux, the predetermined permanent magnet temperature is initially set as the permanent magnet temperature when determining the inductance. After that, the permanent magnet temperature was repeatedly determined by using the permanent magnet temperature determined by the second data application unit to determine the permanent magnet temperature and used for determining the inductance. When the difference between the permanent magnet temperature and the permanent magnet temperature determined by the estimation calculation process is within a predetermined range, the estimation calculation process Thus the estimated the determined the permanent magnet temperature the permanent magnet temperature.

  According to the above method, from the phase current flowing through the rotating machine and the line voltage of the rotating machine, the first data indicating the relationship between the permanent magnet temperature, the phase current and the inductance of the rotating machine, and the magnetic flux with respect to the permanent magnet temperature. The permanent magnet temperature is calculated by the estimation operation process which is a convergence operation using the second data indicating the relationship. In this estimation calculation process, information on current phase is not necessary, and since the permanent magnet temperature is calculated from the phase current and the line voltage that can be measured during rotation of the rotating machine, special control of the rotating machine is required. There is no need to do it. Therefore, the permanent magnet temperature of the rotating machine can be estimated with high accuracy without performing special control on the rotating machine during the operation of the rotating machine.

  ADVANTAGE OF THE INVENTION According to this invention, the permanent magnet temperature of a rotary machine can be estimated with high precision, without performing special control with respect to a rotary machine during operation | movement of a rotary machine.

FIG. 1 is a block diagram showing a schematic configuration of an estimation apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing a graph based on the first data in the present embodiment. FIG. 3 is a diagram showing a graph based on the second data in the present embodiment. FIG. 4 is a flowchart showing a flow of estimation calculation processing in the present embodiment. FIG. 5 is a basic vector diagram of the rotating machine. FIG. 6 is a diagram showing that the second data is changed by the correction process of the second data in the graph of FIG. 3.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, the same or corresponding elements are denoted by the same reference numerals throughout all the drawings, and redundant description will be omitted.

[Schematic configuration]
FIG. 1 is a block diagram showing a schematic configuration of an estimation apparatus according to an embodiment of the present invention. In the present embodiment, the estimation device 1 determines the temperature (permanent magnet temperature T) of the permanent magnet 121 provided in the rotating machine 12 that functions as a synchronous generator (hereinafter referred to as a generator) that rotates in synchronization with the rotation drive device 11. _Mag ) is configured to estimate.

  The rotating machine 12 includes a rotor 12 a including a permanent magnet 121 and a stator 12 b including a coil 122. In addition, although the stator 12b of 6 slots is illustrated in FIG. 1, the number of slots of the rotary machine 12, the number of poles, etc. are not restricted to this, and various adoption is possible. Moreover, various aspects can be adopted for other configurations of the rotating machine 12. The rotating machine 12 rotates in synchronization with the rotary drive 11 and outputs a current generated accordingly.

  The rectifier 13 is electrically connected to the current output portion of the rotating machine 12. The rectifier 13 converts AC power into DC power and supplies power to the load 14. The rotational drive device 11 is controlled by a drive control device (not shown). A voltage converter (DC-DC converter) (not shown) is connected between the rectifier 13 and the load 14 and is converted into a voltage suitable as a power source for the load 14. The load control device 15 performs load control such as power supply to the load 14. In this manner, the system 10 in the present embodiment converts the rotational driving force of the rotational drive device 11 into electric power by the rotating machine 12 and supplies the electric power to the load 14 via the rectifier 13, thereby powering the load 14. It is configured to secure.

  The estimation device 1 illustrated in FIG. 1 includes an input unit 2, a storage unit 3, an arithmetic unit 4, and an output unit 5. The configurations 2 to 5 of the estimation device 1 mutually transmit data via the bus 6. The estimation device 1 may be configured by a control device of the system 10 (for example, a drive control device, a load control device 15 or the like) or a computer provided for estimation calculation processing, or provided separately (remotely) from the system 10 It may be configured by a computer. In addition, the control device of the system 10 exerts a part of the functions constituting the estimation device 1, the remote computer exerts the other functions, and mutual communication of data is performed between the computers by communication means such as wireless communication. It may be configured to be performed.

A current detector 7, a voltage detector 8 and a temperature detector 9 are connected to the input unit 2. The current detector 7 detects the phase current I _u flowing through the rotating machine 12. The voltage detector 8 detects the line voltage V _uv of the rotating machine 12. The temperature detector 9 detects the temperature (coil temperature) T _coil of the coil 122 of the stator 12 b of the rotating machine 12. The values detected by these detectors 7 to 9 are input to the input unit 2. Further, the input device 2 may be configured to be able to input setting values and the like input by the user from a predetermined input device (not shown).

The storage unit 3 stores the information input to the input unit 2. In addition, the storage unit 3 stores an operation program for estimation operation processing, first and second data used for the estimation operation processing, and a phase resistance R _u of the rotary machine 12. In addition, in the storage unit 3, values (for example, values detected by the respective detectors 7 to 9) input to the input unit 2 are also stored.

The first data and the second data are produced by electromagnetic field analysis using the phase resistance R _u and the inductance (winding phase inductance) L _ou at a predetermined set temperature (for example, 20 ° C.) of the rotary machine 12. At this time, the phase resistance R _u and the inductance L _uo of the rotating machine 12 at normal temperature are calculated by actual measurement or electromagnetic field analysis.

The first data is data indicating the relationship between the temperature (permanent magnet temperature) T _mag of the permanent magnet 121 of the rotating machine 12, the phase current I _u, and the inductance L _u of the rotating machine 12. FIG. 2 is a diagram showing a graph based on the first data in the present embodiment. As shown in FIG. 2, the inductance L _u of the rotating machine 12 changes in accordance with changes in the permanent magnet temperature T _mag and the phase current I _u . In FIG. 2, in particular, it is shown that the inductance L _u changes significantly according to the change of the permanent magnet temperature T _mag .

Although FIG. 2 exemplifies a graph in which the permanent magnet temperature T _mag is discontinuous (a graph of the inductance L _u with respect to the phase current I _{u at} each of the three temperatures T 1 to T 3), Data in which the permanent magnet temperature T _mag is continuous (for example, data shown as a three-dimensional map) may be used.

The second data is data indicating the relationship between the permanent magnet temperature T _mag and the magnet flux Ψ _u . FIG. 3 is a diagram showing a graph based on the second data in the present embodiment. As shown in FIG. 3, in the present embodiment, the relationship between the permanent magnet temperature T _mag and the magnet magnetic flux Ψ _u is approximated by a quadratic curve. That is, the graph in FIG. 3 is represented by Ψ _u = −A · T _mag ² −B · T _mag + C (A, B and C are positive constants).

  Note that the first data and the second data may be continuous values (values that can be graphed or functioned) using approximation as shown in FIGS. 2 and 3 or configured as discrete table data May be.

Arithmetic unit 4 executes estimation operation processing for estimating permanent magnet temperature T _mag of rotating machine 12 based on various information stored in storage unit 3. For this purpose, the computing unit 4 exerts the functions of the waveform conversion processing unit 41, the estimation computation processing unit 42, the second data correction unit 43, and the like based on the computation program.

[Estimate operation processing]
The estimation calculation process in the present embodiment will be described below. FIG. 4 is a flowchart showing a flow of estimation calculation processing in the present embodiment. First, when the rotating machine 12 is rotating and current is flowing to the rotating machine 12 (when current is flowing to the rectifier 13), the computing unit 4 detects the phase current I _u detected by the current detector 7 and The line voltage V _uv detected by the voltage detector 8 is acquired (step S1). When the system 10 in the present embodiment is a moving object such as an aircraft, when the rotating machine 12 is rotating and current flows, it means that the moving object is moving (flying, sailing, traveling, etc.) . The rotational speed of the rotating machine 12 at the time of detection of the phase current I _u and the line voltage V _uv may be indefinite or constant.

The waveform conversion processing unit 41 performs waveform conversion processing on the acquired phase current I _u and line voltage V _uv (step S2). More specifically, the waveform conversion processing unit 41 extracts the fundamental wave component of the phase current I _u from the phase current I _u , the fundamental wave component of the line voltage V _uv from the line voltage V _uv , and the angular velocity of the rotating machine 12 Take out ω. Each fundamental component shows waveforms obtained by removing a harmonic component from the waveform of the original phase current I _u and line voltage V _uv. For example, discrete Fourier transform and frequency / voltage conversion (F / V conversion) are used to extract the fundamental wave component. Assuming that the original waveform is f (x), the fundamental wave component f1 (x) is expressed as follows. However, N shows the number of samplings.

The waveform conversion processing unit 41 applies the above equations to the original waveforms of the phase current I _u and the line voltage V _uv . Waveform conversion processing unit 41 fetches the current amplitude _{I u1} and current phase theta _Iu1 from the fundamental component of the phase current _{I u} obtained f1 (x). Similarly, the waveform conversion processing unit 41 takes out the voltage amplitude V _uv1 and the voltage phase θ _Vuv1 from the fundamental wave component f1 (x) of the obtained line voltage V _uv . Further, the waveform conversion processing unit 41 calculates the phase difference φ = θ _Vuv1 −θ _Iu1 of the line voltage (voltage amplitude V _uv1 ) to the phase current (current amplitude I _u1 ) from the current phase θ _Iu1 and the voltage phase θ _Vuv1. . Further, the waveform conversion processing unit 41 takes out the rotational speed N _gen [rpm] of the rotating machine 12 from the fundamental wave component f1 (x) of the line voltage V _uv . Furthermore, the waveform conversion processing unit 41 generates the angular velocity ω [rad / s] of the rotating machine 12 from the rotation speed N _gen . The angular velocity ω is represented by ω = 2π (N _gen / 60).

The estimation arithmetic processing unit 42 performs estimation arithmetic processing for estimating the permanent magnet temperature T _mag . To this end, the estimation arithmetic processing unit 42 includes functions of a first data application unit 421, a magnet magnetic flux calculation unit 422, a second data application unit 423, and the like.

The first data application unit 421 executes convergence calculation of the permanent magnet temperature T _mag as estimation calculation processing. Therefore, the first data application unit 421 sets T _mag (old) to T 0 as an initial value (old value) to be compared with the permanent magnet temperature (step S 3). The initial value T0 is set to, for example, a temperature (eg, 28 ° C. or the like) at which the normal temperature is set.

The first data application unit 421 calculates the inductance L _u using the set initial value T _mag (old) = T 0 and the first data (step S 4). More specifically, based on the first data, the first data application unit 421 determines the inductance L at the permanent magnet temperature T _mag (old) from the fundamental wave component (amplitude I _u1 ) of the phase current extracted by the waveform conversion process. Determine _u (step S5). As described above, since the first data indicates the relationship between the phase current I _u , the permanent magnet temperature T _mag and the inductance L _u , the phase current I _u is I _u1 and the permanent magnet temperature T _mag is The inductance L _u in the case of T _mag (old) is determined from the first data.

The magnet flux calculation unit 422 calculates the fundamental wave component (I _u1 , θ _Iu1 ) of the phase current extracted by the waveform conversion process, the fundamental wave component (V _uv1 , θ _Vuv1 ) of the line voltage, the angular velocity ω, and the first data application unit A magnet flux Ψ _u is calculated from the inductance L _u determined at 421 and the phase resistance R _u of the rotary machine 12 stored in the memory 3 (step S5).

FIG. 5 is a basic vector diagram of the rotating machine. In FIG. 5, the electromotive force E _u1 of the rotating machine 12 is represented by E _u1 = ωΨ _u . Therefore, the magnet flux Ψ _u is Ψ _u = E _u1 / ω. Further, the magnet flux Ψ _u is shown as follows from the vector diagram of FIG.

The second data application unit 423 determines the permanent magnet temperature T _mag from the calculated magnet flux Ψ _u based on the second data (step S6). In order to distinguish the determined permanent magnet temperature T _mag from the original T _mag (old), let T _mag (new). As described above, since the second data indicates the relationship between the permanent magnet temperature T _mag and the magnet magnetic flux Ψ _u , the permanent magnet temperature T _mag (when the magnet magnetic flux Ψ _u is a value calculated as described above) new) is obtained from the second data.

The estimation arithmetic processing unit 42 determines that the difference between the permanent magnet temperature T _mag (old) used when determining the inductance L _u (step S 4) and the permanent magnet temperature T _mag (new) determined by the estimation arithmetic processing is predetermined. It is determined whether, for example, T _mag (new) −T _mag (old) is less than a predetermined value T _ref (step S7).

If the difference between the permanent magnet temperatures is not within the predetermined range (No in step S7), the estimation calculation processing unit 42 calculates the permanent magnet temperature T _mag (old) at the time of determining the inductance L _u again by this estimation calculation. It sets to permanent magnet temperature _Tmag (new) determined by the 2nd data application part 423 by processing (Step S8). Then, the estimation calculation processing unit 42 performs an estimation calculation process using the updated permanent magnet temperature T _mag (old) again to determine a new permanent magnet temperature T _mag (new) (steps S4 to S6). ).

In this manner, the estimation calculation processing unit 42 initially uses the initial value T0 of the permanent magnet temperature determined in advance as the permanent magnet temperature T _mag (old) at the time of determining the inductance L _u . with 2 are determined by the data application unit 423 (previous) permanent magnet temperature _T mag (new new), by performing the repeated estimation calculation processing, determines a new permanent magnet temperature _T mag (new new). In the first determination using the initial value T0 of the permanent magnet temperature as the permanent magnet temperature T _mag (old) at the time of determining the inductance L _u in the determination of the step S7, the step S7 does not actually make the determination. The process may proceed to step S8 as the permanent magnet temperature difference is not within the predetermined range.

If the difference between the permanent magnet temperatures falls within the predetermined range (Yes in step S7), the estimation operation processing unit 42 estimates the (most recent) permanent magnet temperature T _mag (new) determined by the estimation operation process. The output unit 5 outputs the obtained permanent magnet temperature T _mag from the output unit 5 (step S9).

In the present embodiment, the output device 5 is connected to the load control device 15. The permanent magnet temperature T _mag estimated by the estimation device 1 is input to the load control device 15. The load control device 15 controls the power supply to the load 14 according to the change of the permanent magnet temperature T _mag . For example, the load control device 15 changes the maximum value of the power supplied to the load 14 (available to the load 14) or changes the number of loads 14 that can supply power among the plurality of loads 14.

Additionally or alternatively, the permanent magnet temperature T _mag output from the output device 5 may be input to the drive control device of the rotary drive device 11. In this case, the drive control device reflects the estimated permanent magnet temperature T _mag in the control algorithm of the rotary drive 11, and the permanent magnet 121 of the rotary machine 12 does not irreversibly demagnetize during the operation of the rotary drive 11. In this way, the rotary drive 11 may be controlled. Thereby, the permanent magnet 121 can be prevented from being irreversibly demagnetized, and the region where the permanent magnet 121 is not irreversibly demagnetized can be clarified so that the performance of the rotary drive device 11 can be maximized. .

According to the above arrangement, the relationship between the line voltage _{V uv} phase current flowing through the rotating machine 12 _{I u} and the rotating machine 12, the permanent magnet temperature _{T mag} and the phase current _{I u} and the inductance _{L u} of the rotating machine 12 using the second data showing the relationship for magnetic flux [psi _u for the first data and the permanent magnet temperature _{T mag} showing the permanent magnet temperature _{T mag (T mag (new)} ) is calculated by the convergence arithmetic estimation processing Ru. Since the inductance L _u of the rotating machine 12 varies not only with the phase current I _u but also with the permanent magnet temperature T _mag , the convergence calculation including the inductance L _u is carried out by the permanent magnet temperature T _mag of the inductance L _u An estimation calculation of the permanent magnet temperature T _mag can also be performed in consideration of the change. This is particularly effective when estimating the permanent magnet temperature T _mag of the rotating machine 12 having a larger reactance component than the resistance component when estimating the permanent magnet temperature T _mag of the rotating machine 12 used at a high rotation speed. It is

Further, in this estimation calculation processing, since it is not necessary to control the current phase, the permanent magnet temperature T _mag is calculated from the phase current I _u and the line voltage V _{uv which} can be measured during rotation of the rotating machine 12 There is no need to control the rotating machine 12 specially. Therefore, the permanent magnet temperature T _mag of the rotary machine 12 can be estimated with high accuracy without performing special control on the rotary machine 12 during the operation of the rotary machine 12.

In particular, in the case where the rectifier 13 is electrically connected to the rotating machine 12 which is a generator as in the present embodiment, the rectifier 13 is a passive current converter. The current phase can not be controlled arbitrarily for the machine 12. On the other hand, in the above embodiment, since it is not necessary to control the current phase arbitrarily, the permanent magnet temperature of the rotating machine 12 which is the generator is also in the system in which the rectifier 13 is electrically connected to the rotating machine 12 which is the generator. T _mag can be estimated with high accuracy.

In addition, by performing waveform conversion processing on the phase current I _u and the line voltage V _uv detected by the current detector 7 and the voltage detector 8, a permanent magnet is obtained using the fundamental wave component excluding the harmonic component. Since the temperature T _mag is estimated, it is possible to prevent deterioration in the estimation accuracy of the permanent magnet temperature T _mag due to harmonics caused by switching for power conversion in the rectifier 13.

Further, according to the above configuration, it is possible to estimate the permanent magnet temperature T _mag with high accuracy during the rotation of the rotary machine 12 regardless of the number of rotations of the rotary machine 12 (in the case of high or low). Further, in the rotating machine 12 which is a generator, the permanent magnet temperature T _mag can be estimated with high accuracy regardless of the amount of generated power (load current). Furthermore, even when there is a difference between the permanent magnet temperature _Tmag and the coil temperature _Tcoil , the permanent magnet temperature _Tmag can be estimated with high accuracy. As described above, since the permanent magnet temperature T _mag can be estimated with high accuracy under any condition regardless of the state of the rotating machine 12, the rotating machine 12 used for various applications and under various environments The present invention is suitably applicable to the rotating machine 12 that is set.

Moreover, according to the above configuration, in a system capable of detecting at least the phase current I _u and the line voltage V _uv of the rotating machine 12, the estimation can be performed with high accuracy simply by causing the existing computer to execute the calculation program. The calculation processing of the permanent magnet temperature T _mag can be realized without adding any special equipment.

[2nd data correction process]
Hereinafter, additional processing for making the above estimation calculation processing more accurate will be described. First, the correction process of the second data in consideration of the individual difference of the magnet magnetic force of the permanent magnet 121 attached to the rotating machine 12 will be described.

In the present embodiment, the second data correction unit 43 sets the permanent magnet temperature of the rotary machine 12 before the estimation device 1 estimates the permanent magnet temperature T _mag of the rotary machine 12 (before starting step S1 shown in FIG. 4). The second data is corrected based on the individual difference of the magnet 121. For this reason, the second data correction unit 43 determines the line voltage V _uva when the rotating machine 12 is rotating and no current flows in the rotating machine 12 (a state in which the rotating machine 12 is rotated with no load). And the coil temperature T _coil .

  At this time, the wiring between the rotating machine 12 and the rectifier 13 or between the rectifier 13 and the load 14 is previously cut off by a circuit breaker (not shown). By rotating the rotating machine 12 in this state, a state in which no current flows in the rotating machine 12 while the rotating machine 12 is rotating is realized. As in the present embodiment, when the system 10 is a mobile object such as an aircraft, the correction processing of the second data is performed, for example, at the time of landing (during aircraft maintenance or aircraft delivery, etc.).

The second data correction unit 43 calculates the magnet magnetic flux Ψ _ua from the detected line voltage V _uva (the phase current I _{ua at} this time is 0) using the equation (2). The second data correction unit 43 corrects the second data so that the calculated magnet magnetic flux _Ψua becomes the magnet flux when the permanent magnet temperature T _mag is the coil temperature T _coil . Here, the coil temperature T _coil when the rotating machine 12 is unloaded is considered to be approximately equal to the permanent magnet temperature T _mag at this time.

  FIG. 6 is a diagram showing that the second data is changed by the correction process of the second data in the graph of FIG. 3. The second data shown in the graph of FIG. 3 is represented by a quadratic function as described above.

For example, in the original (before correction) second data shown by an imaginary line in FIG. 6, the magnet flux at the coil temperature T _coil is Ψ _uo . On the other hand, when the calculated magnet flux _Ψua becomes a value different from _uouo (lower in FIG. 6), the second data correction unit 43 generates the graph of FIG. 3 indicated by the second data. Is translated in the direction of the axis (longitudinal axis) of the magnet flux. In the example of FIG. 6, a quadratic function in the second data after ^{_{correction, Ψ u = -A · T mag}} 2 -B · T mag Ψ u = shown by the solid line in FIG. 6 + C -A _{· T mag} It is corrected to ^2- B · T _mag + C ′ (C ′ = C− (Ψ _uo −Ψ _ua )).

According to this, it is possible to correct the second data according to the individual difference of the magnet magnetic force of the permanent magnet 121 attached to the rotating machine 12 for estimating the permanent magnet temperature T _mag . Therefore, permanent magnet temperature T _mag can be estimated with higher accuracy.

Further, in this example, the graph indicated by the second data is moved in parallel in the axial direction of the magnet magnetic flux. This is based on the assumption that the magnitude of the magnet flux Ψ _u may change due to the individual differences of the permanent magnets 121 but the overall tendency (the behavior as a quadratic function in this example) hardly changes. . By correcting the second data by parallel movement of the graph, it is easy to simply measure the second data according to the individual difference of the permanent magnet 121 simply by measuring the combination of one permanent magnet temperature T _mag and the magnet magnetic flux Ψ _u. It can be corrected.

In the above example, the graph indicated by the second data is translated in the axial direction of the magnet flux, but the correction mode of the second data is not limited to this. For example, if the second data is a discrete table data, it may be applied to the rate of change of magnetic flux [psi _ua calculated for the original magnetic flux [psi _uo to all of the plurality of values of magnetic flux [psi _u. In this case, for example, a plurality of values Ti (i = 1,2, ..., n) of the permanent magnet temperature _{T mag} discrete first plurality of values Ψi magnet flux [psi _u is associated to each In the two data, when Ψ _ua −Ψ _uo ) / Ψ _uo = −0.02, each of a plurality of values Ψi of the magnetic flux Ψ _u may be multiplied by −0.02.

  The correction process of the second data as described above may be performed every time the system 10 starts (before moving the moving object), or periodically (every time the system is started a predetermined number of times) when the system 10 starts. It may be performed only once when the system 10 is initially activated.

Correction process of phase resistance
Hereinafter, the correction process of the phase resistance R _u will be described as a second example of the additional process for making the estimation calculation process more accurate.

In the present embodiment, the magnet magnetic flux calculation unit 422 corrects the phase resistance R _u based on the detected coil temperature T _coil . For example, in the above estimation calculation process (flow chart of FIG. 4), the arithmetic unit 4 adds the line voltage V _uv and the phase current I _u in step S1 to the temperature detector 9 during rotation of the rotary machine 12 and during energization. The detected coil temperature T _coil is obtained. After that, before calculating the magnet flux 相_u (between step S 1 and step S 5), the magnet flux calculation unit 422 calculates the phase resistance stored in advance in the memory 3 based on the coil temperature T _coil. Correct R _u .

For example, when the phase resistance R _u stored in advance in the memory 3 is a resistance value at the temperature T _s , the corrected phase resistance R _ua is represented as follows, assuming that the temperature coefficient of resistance α.

The phase resistance R _ua corrected in this manner is stored in the memory 3. In step S5, the magnet flux calculation unit 422 calculates the magnet flux Ψ _u using the phase resistance R _ua after the correction. That is, the magnet magnetic flux calculation unit 422 calculates the magnet magnetic flux Ψ _u by replacing R _u in Formula (2) with R _ua .

According to this, it is possible to correct the phase resistance R _u of the rotary machine 12 to a value at the time of estimating the permanent magnet temperature T _mag . Therefore, permanent magnet temperature T _mag can be estimated with higher accuracy. This is particularly the like when estimating the permanent magnet temperature T _mag of the rotating machine 12 used in the low rotational speed, when estimating the permanent magnet temperature T _mag of the rotating machine 12 resistance component is larger than the reactance component It is effective.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, A various improvement, change, and correction are possible within the range which does not deviate from the meaning.

  For example, although the above-mentioned embodiment explained composition which is connected to rotation drive 11 of an aircraft and presumes permanent magnet temperature of rotation machine 12 which functions as a generator, it is not restricted to this. For example, the rotating machine 12 may be a generator of a movable body such as a ship or a vehicle, or a generator installed on the ground, or may be an electric motor generating a rotational driving force. Thus, the rotating machine 12 may be a generator or an electric motor.

In particular, the rotating machine 12 for special environment where the permanent magnet temperature T _mag is likely to be high, such as the rotating machine 12 driven under high speed rotation and / or vacuum environment, and the environment, such as the rotating machine 12 for aircraft Remote monitoring of permanent magnet temperature is important, as in rotating machine 12 where conditions change frequently and it is difficult to estimate permanent magnet temperature T _mag based on environmental conditions, and rotating machine 12 using IoT technology It is effective to estimate the permanent magnet temperature T _mag in the rotating machine 12.

  The rotating machine 12 may be connected to a power conversion device other than the rectifier 13 exemplified in the above embodiment, such as an inverter or a converter using a PWM method or the like.

  Further, in the above embodiment, the aspect in which the waveform conversion processing unit 41 and the estimation operation processing unit 42 are realized as the function of one computing unit 4 has been described, but instead, the waveform conversion processing unit 41 and estimation are performed. The arithmetic processing unit 42 may be realized by separate computing units (computers).

In the above embodiment, the waveform conversion processing unit 41 performs the Fourier transform to extract the fundamental wave components of the phase current I _u and the line voltage V _uv , but the present invention is not limited to this. Each fundamental wave component may be extracted by applying a low pass filter to the phase current I _u and the line voltage V _uv detected by the detector.

Hereinafter, the result of the test which estimated permanent magnet temperature _Tmag using the presumed arithmetic processing by the said embodiment with respect to an actual generator, and calculated _| required the error with the value which measured permanent magnet temperature is shown. In this test, in each of the two types of states where the generated power is large and medium in one generator, when the number of revolutions of the generator is high, medium and low, 3 A total of six states were tested, each of which was a combination of types. In the test, the phase current I _u and the line voltage V _uv of the generator in each state are measured, the estimation arithmetic processing is performed to estimate the permanent magnet temperature T _mag , and the permanent magnet temperature is actually measured and estimated. The error between the measured value and the measured value was calculated.

First, as a comparative example, when the inductance L _u is set to a fixed value in the estimation calculation process (in step S8 of FIG. 4, the updated permanent magnet temperature T _mag (new) is set to the permanent magnet temperature T _mag (old) The errors in each state) when estimation of the permanent magnet temperature T _mag is performed without the above are shown in Table 1 below.

As shown in Table 1, when the inductance L _u was not reflected in the convergence calculation, an error was recognized in any state (test No.).

On the other hand, based on the above embodiment, the error in each state when estimating permanent magnet temperature T _mag while updating inductance L _{u based} on updated permanent magnet temperature T _mag (new) in the estimation calculation process Is shown in Table 2 below.

As shown in Table 2, in the estimation calculation process according to the above-described embodiment, the inductance L _u is reflected in the convergence calculation, which makes it possible to compare with the comparative example (Table 1) in any state (test No.). The result is that the error is greatly reduced.

From the above, it has been shown that the permanent magnet temperature T _mag can be estimated with high accuracy in the estimation calculation process in the present embodiment.

  The present invention is useful for providing an estimation apparatus and estimation method capable of estimating the permanent magnet temperature of a rotating machine with high accuracy without performing special control on the rotating machine during operation of the rotating machine. .

DESCRIPTION OF SYMBOLS 1 Estimating device 3 Memory 4 Arithmetic unit 7 Current detector 8 Voltage detector 9 Temperature detector 12 Rotating machine 13 Rectifier 41 Waveform conversion processing unit 42 Estimation calculation processing unit 43 Second data correction unit 121 Permanent magnet 421 First data application Part 422 Magnet magnetic flux calculation part 423 Second data application part

Claims (6)

An estimation apparatus for estimating permanent magnet temperature in a rotating machine provided with a permanent magnet, comprising:
A storage for storing the first data and the second data;
A current detector that detects a phase current flowing through the rotating machine;
A voltage detector for detecting a line voltage of the rotating machine;
And a computing unit,
The first data is data indicating a relationship between the permanent magnet temperature, the phase current, and the inductance of the rotating machine,
The second data is data indicating a relation of the magnet magnetic flux to the permanent magnet temperature,
The computing unit is
A waveform conversion processing unit that performs a waveform conversion process that extracts the fundamental wave component of the phase current from the detected phase current and extracts the fundamental wave component of the line voltage and the angular velocity of the rotating machine from the detected line voltage When,
An estimation operation processing unit that performs estimation operation processing for estimating the permanent magnet temperature;
The estimation operation processing unit
A first data application unit that determines the inductance at the permanent magnet temperature from a fundamental wave component of the phase current extracted by the waveform conversion process based on the first data;
The magnet from the fundamental wave component of the phase current extracted by the waveform conversion process, the fundamental wave component of the line voltage, the angular velocity, the inductance determined by the first data application unit, and the phase resistance of the rotating machine A magnetic flux calculating unit that calculates a magnetic flux;
And a second data application unit that determines the permanent magnet temperature from the calculated magnet magnetic flux based on the second data.
The estimation arithmetic processing unit initially uses the permanent magnet temperature determined in advance as the permanent magnet temperature at the time of determining the inductance, and thereafter the permanent magnet temperature determined by the second data application unit The permanent magnet temperature is determined by repeatedly performing the estimation operation process using the above, and the permanent magnet temperature used when determining the inductance and the permanent magnet temperature determined by the estimation operation process The estimation apparatus which outputs the said permanent magnet temperature determined by the said estimation arithmetic processing as said estimated permanent magnet temperature, when a difference becomes in a predetermined | prescribed range.   The estimation device according to claim 1, wherein the phase current and the line voltage used for the waveform conversion process are values detected when the rotating machine is rotating and current flows in the rotating machine. . The rotating machine is a generator,
The estimation device according to claim 1, wherein the generator is electrically connected to a rectifier. A temperature detector for detecting a coil temperature of the rotating machine;
The arithmetic unit calculates the magnet magnetic flux from the line voltage detected when the rotating machine is rotating and no current flows in the rotating machine, and the calculated magnet flux is the temperature of the permanent magnet The estimation apparatus according to any one of claims 1 to 3, further comprising: a second data correction unit configured to correct the second data such that a magnet magnetic flux when the coil temperature is the coil temperature. A temperature detector for detecting a coil temperature of the rotating machine;
The estimation device according to any one of claims 1 to 4, wherein the magnet magnetic flux calculation unit corrects the phase resistance based on the detected coil temperature. An estimation method for estimating permanent magnet temperature in a rotating machine provided with a permanent magnet, comprising:
Detecting a phase current flowing through the rotating machine;
Detect the line voltage of the rotating machine,
The fundamental wave component of the phase current is extracted from the detected phase current, and the waveform conversion process is performed to extract the fundamental wave component of the line voltage and the angular velocity of the rotating machine from the detected line voltage.
Performing estimation arithmetic processing for estimating the permanent magnet temperature;
The estimation operation process is
Based on first data indicating the relationship between the permanent magnet temperature, the phase current, and the inductance of the rotating machine, the fundamental wave component of the phase current extracted by the waveform conversion process is used at the permanent magnet temperature Determine the inductance,
The magnet magnetic flux is calculated from the fundamental wave component of the phase current extracted by the waveform conversion process, the fundamental wave component of the line voltage, the angular velocity, the determined inductance, and the phase resistance of the rotating machine,
Determining the permanent magnet temperature from the calculated magnet flux based on second data indicating a relationship of the magnet flux to the permanent magnet temperature;
As the permanent magnet temperature at the time of determining the inductance, the permanent magnet temperature initially determined in advance is used, and thereafter, the estimation is repeatedly performed using the permanent magnet temperature determined by the second data application unit. By performing arithmetic processing, the permanent magnet temperature is determined, and the difference between the permanent magnet temperature used in determining the inductance and the permanent magnet temperature determined by the estimation arithmetic processing falls within a predetermined range. When it becomes, the estimation method which makes the said permanent magnet temperature determined by the said estimation arithmetic processing the said permanent magnet temperature estimated.

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